The Cisco 1900 Series Integrated Services Routers (ISRs) are modular routers with LAN and WAN connections that can be configured by means of interchangeable interface cards and internal service modules (ISMs). The series currently consists of the 1905, 1921, 1941, and 1941W (wireless) models. The 1941W is Wi-Fi CERTIFIED™ and 802.11a/b/g/n-compliant. The modular design of the routers provides flexibility, allowing you to configure your router according to your needs.